Low Vitamin D Linked to Severe Strokes

Stroke patients with low vitamin D have been found to suffer more severe strokes and have poorer health in the months following a stroke, than those who have normal vitamin D levels, according to research presented at last year’s American Stroke Association’s International Stroke Conference.

In past studies on neurovascular injury low vitamin D levels have been linked to damage to the major blood vessels supplying the brain, brainstem and upper spinal cord.

The Study That Linked Low Vitamin D To Severe Stroke:

Vitamin D

“Many of the people we consider at high risk for developing stroke have low vitamin D levels. Understanding the link between stroke severity and vitamin D status will help us determine if we should treat this vitamin deficiency in these high-risk patients,” says Nils Henninger, M.D., senior study author and assistant professor of neurology and psychiatry at University of Massachusetts Medical School in Worchester.

Dr Henninger and his team studied whether or not low blood levels of 25-hydroxyvitamin D in 96 stroke patients, who were treated between January 2013 and January 2014 at an unnamed U.S. hospital, were indicative of the onset of Ischemtic stroke (stroke occurring as the result of a blockage in the blood vessels which supply blood to the brain) as well as poor health during recovery.

vitamin D

The study found that:

  • “Overall, patients who had low vitamin D levels –defined as less than 30 nanograms per milliliter (ng/mL) – had about two-times larger areas of dead tissue resulting from obstruction of the blood supply compared to patients with normal levels of the vitamin,” explains Dr Henninger.
  • “This association was similar among patients who suffered lacunar strokes (in which the small, intricate arteries of the brain are affected) and patients with non-lacunar strokes (such as those caused by carotid disease or by a clot that originated elsewhere in the body),”he notes.
  • “For each 10 ng/mL reduction in vitamin D level, the chance for healthy recovery in the three months following stroke decreased by almost half, regardless of the patient’s age or initial stroke severity,” says Dr Henniger.

“It’s too early to draw firm conclusions from our small study, and patients should discuss the need for vitamin D supplementation with their physician,” Henninger says. “However, the results do provide the impetus for further rigorous investigations into the association of vitamin D status and stroke severity. If our findings are replicated, the next logical step may be to test whether supplementation can protect patients at high risk for stroke.”